Control means for hydraulic presses and the like



April 18, 1939. 'A. F. (SINCLAIR CONTROL MEANS FOR HYDRAULIC PRESSES AND THE LIKE 3 SheetS -Sheet 1 Filed Sept. 13, 1954 w @EW 7 w 4 9 52.: 7 t m W QIJ I 8 HH I H i m 5 4 4 E: 3 y\ 7 N6, INN\\ .J/ 2 L. a z w m y t w m m QLM mkt A4/ 5/ a t w u I 6 M v i w 6 5 Y 7 5 I 5 my; w m 9 4 w a e %%w 5 56 INVFNTOR.

M a J y M a C r n ATTORNEYS,

CONTROL MEANS FOR HYDRAULIC PRESSES AND THE LIKE Fild Sept. 13, 1934 3 Sheets-Shet 2 M R M w o T a N g a m M w m w 5 q. H mm mm 5 A i8 Q i a Q. .2 h a [1/ r 7 11 l I I whfl 0M 9% E. g MN mwwbfll. t. a, z /.No b w w m T RAKANN- \w m kn g CONTROL MEANS FOR HYDRAULIC PRESSES AND THE LIKE- Filed Sept. 13, 1934 3 Sheets-Sheet 3 S. M ma 0am E7. 0 W i A I J a 0 f MB O n 8 7- 8 9 d m M W 7 m%% mmwm m 8 9 j 5 9 W/ 9 m Patented Apr. 18, 1939 PAT F Fl CE CONTROL MEANS FOR-" HYDRAULIC PRESSESAND LIKE:

Archibald F. Sinclair, Ouyahoga. 01116 Application September-13, 193, Srill N6. 74-33873 2' Claims.

particularly to means whereby such presses may be operated from two independent'sources of fluid sure may be so controlled-that the piston portion of the hydraulic press may be moved into engagement with the head portion thereof under relatively low pressure and after the movable element has been so brought into engagement with the-fixed head, fluid from an independent source under high pressure may be automaticallycutin to hold said movable elementin such posi-- 'tion.

It'isa further object of my invention to-pro- -0 vide control means of "the character described whereby the movement of the ram in the'press may be arrested at any selected position and heldin such position under thecontrol of the operator. It is'a further object of my invention to provide novel means for the energization of the control means for'hydraulic presses. Other objectsof my invention will appear as the descriptionproceeds.

30 To" the accomplishment of the foregoing and" related ends, said invention, then consists of the means hereinafter fully described and particu-- larly pointed out in the claims, the annexed draw ings and the following description settingfo'rth .5= in detail certain mechanism embodying the invention, such disclosed means constituting, however,but' one of various mechanical forms in which the principle of the invention may be used.

In said annexed drawings:

Fig.1 is a transverse sectional view of one form of control valve constructed in accordancewith the principles of my invention and comprising one unit of my control system; Fig. 2 is adiagrammatic representation of a control circuit for hydraulic presses showing another form of the main control valve; Fig. 3'is a fragmentary sectional view of a valve similar to that illustrated in Figs; 1 and 2 showing, however, a difierent means for actuating the main valve member therein; Fig. 4 is a view similarto Fig. 3-but showing a slightly different relationship between the parts illustrated in said last named figure; Figs. 5 and 6' are respectively fragmentary sectional views drawn toan enlarged scale of portions of '55} theapparatusrillustrated in Figs. 3 and 4; illus- This invention relates as indicated to controlmeans'for hydraulic presses and the like and more trating' more: particularly the relationship between the mainvalve: stem and its actuating means and support; Fig; 7 is'a part side elevation'a'l, .part-section'alview'of a valve similar to that illustrate'drinil i'gs; 1: and 2 but' showing as- 6 sociated therewith 'auxiliary control valves having a slightlydi-fierent construction'than those shown in the previbus figures; Fig; 81s a fragmenta'ry sectional view: drawn to an enlarged scale of the high' pressure check' 'valve illustrated 1 at the' left it'l -F1237: Fig. 9 is: a transverse sectional vi'ewpf the' central air: valve shown in the system inciiided in Fig. 2; an'd Fig. 10 is a diagrammatic -representationof a" complete control system for hydraulic presses embodying the sev-. eral 1 features of thisinvention.

Referring now' moi'e specifically to the drawings it is believed advisable in a description of the principles ot invention to first describe the main control val'v'eforniing-i the major portion of such system: While the'sy'stem is generally illustrated in Figs. 2 and 9, it is believed best, therei'cra to flrst'describethe main valve construction'as' illustrate-dun Fig. 1, since the principles'of such construction'or at least the major portion of= 's\1ch construction are included in systems illustrated in the: above" mentioned figures.

Referring now more speciflcally'to Fig; 1, the valVe hereih ilhistiatdcomprisesa body or casing, generally 'indicated at I, which'along with removable headers 2=and 3, respectively forms a chamberor passage which-tor convenience of description, will be-reterred to as consisting of terminal portlons"4 and 5 and a' central portion 6. The casin'g l 'li'a's a lateral extension generally indicated-st l; which, along-with a removable header" 8?? provides an inlet passage 9 i for fluid under relativel'ydow pressure; 7

Associated with the casing land threadably secured'i thcreto is a high pressure line check 40 valve, generallyindlcated at Hi? It may be pointed out that iii a specific installation, the valve structure-illustrated in" 1 is connected in the control'system for a'hydraulic press in the followingmanner: 'A" conduit such as a pipe car- 5 rying liquid"under250 pounds pressure is connected' at I'li A wasteconduit carrying spent fluid" away-from thepress' is' connected at l2. A conduit carryi'hgfluid under the'pressure of two thousand pciinds'p'er square inch is connectedat I 3. The casirig'l'is provided with an opening I4 leading into thecentral portion 6 of the cham ber within the-casing-eand intosuch opening l4 is-secured aconduit leadingirom the valve to the hydraulic press cylinder with which the valve is associated.

The lateral extension 1 of the main casing I is provided with a tapered annular valve seat I5 upon which normally rests a check valve I6. The stem of the check valve I6 extends movably through a retaining ring I1 and at its upper end has a piston member I8 secured thereto. The piston member I8 operates in a cylindrical cavity I9 and thus serves as a dash-pot for the check valve '6.

The main chamber in the casing I is, as previ-v ously indicated, divided into three portions, i. e., terminal portions 4 and 5 and the central portion 6. Separating the central and terminal portions are annular valve inserts 20 and 2I.,the former separating chamber portions5 an'd'B and the latter separating chamber portions 4. and 6. For

facility in manufacture both inserts ZIland 2I The insert 20 is prohave been made identical. vided with a tapered annular valve seat 22 and the insert 2| ,is provided with a similar valve seat 23, both of such seats facing towards each other. Associated with the seats 22 and 23 and extending axially towards each other therefrom are annular skirts 24 and 25, the function of which will be hereinafter more fully explained.

Extending into the chamber in the casing I is a valve stem 26 which has a valve member or block 21 secured at one end by means of the nut 28. The valve block 21' isat opposite sides provided with valve seats 29 and 30 respectively adapted to engage valve seats 22 and 23 and thus alternately close the passage therethrough.

The upper end 3I of the valve stem 26 is secured to a plunger 32.by means of a lock nut 33 and a dowel 34. The opening through which the plunger 32 extends out of the casing I is provided with a packing ring, generally indicated at 35 which serves to prevent the escape of fluid.

from the chamber within the jlcasing Il past the plunger 32. j

The head is provided with ayoked extension 36 which, at its upper end,supports a; cup-shaped member generally indicated at 31. -A flexible fluid-impervious diaphragm 38, generally of disclike shape, is secured by means of an annular ring 39 to the member 31. I

Secured to the plunger 32 by means of a pin 40 is a presser head 4 I ,which, under the expanding influence of the spring 42 tends to force the diaphragm 38 into engagement with the head 31. The head 31 is provided with a fluid ingress ori-. fice 43 by which fluid under pressure maybe introduced to the space between the diaphragm 38 and the head 31 so as to'force the presser head 4 I downwardly and accordingly movethe valve block 21 axially within the chamber in the casing I. The spring 42 at one end seats "against the yoke member 36 and atits other end against a thimble 44 which bears against the presser head 4I through the lock nuts 45 which are employed to secure the stem 40 to the presser head 4|.

As previously indicated, the casing I has a high pressure line check valve generally indicated at I associated therewith. This check valve comprises a casing 46 in which is formed a threaded opening I3 for connection with a conduit carrying fluid under relatively high pressure.

The casing II! also includes an exteriorly threaded extension 41 Which may be screwed into a suitable aperture provided therefor in the casing I. The casing 46 is provided with a central bore 48, the upper end of which is 'closed by means of a head 49 removably secured to the casing 46 ,a plunger 56 urged downwardly under the in- "fluence of a spring 51.

The spring 51, at its upper end, seats against a plate 58 which is adjustably secured in any desired position by means of the set screw 59. A packing gland 60 is carried by the casing 46 and singly engages the piston member 56 to prevent the escape of fluid past such piston member. The movable piston member 56, the stationary member I and the yoke member 55 are provided with substantially aligned openings wherein are positioned rocker arms 6|. These rocker arms are provided with a plurality of longitudinally spaced arcuate projections against which the members 56, 5I and 55 seat.

The operation in use of the valve assembly illustrated in Fig. 1 may be briefly described as follows:When the press is standing idle, the parts will be in the position illustrated in the drawing, i. e., the closure member 21 will be in engagement with the valve seat 36, closing the passage therethrough. Water under low pressure admitted through the passage II by the check valve I6 fills the chamber 4. Such water under pressure tends to force the closure member, 21 downwardly, and the stem 32 upwardly out of the casing. While the closure member 21 has the same or a larger diameter than the stem 32 where the .latter leaves the casing the closure member. will, nevertheless be held on its valve seat by means of the spring 42. The various parts of the valve will, therefore, remain in the position illustrated in Fig. 1 until fluid under pressure is introduced through the passage 43 between the space defined by the diaphragm 38 and a cup-shaped head 31. When thefiuid is thus introduced the head AI will be moved downwardly against the action of spring 42 and the closure member 21 moved from its position in engagement with the seat 36 into engagement with the lower valve seat 22. In its travel from the upper valve seat 36to the lower valve seat 22, the closure member 21 enters the skirt 24 before it leaves the skirt 25 so that at no time may water from the low pressure source of supply flow directly out of the waste passage 5 which would be the case were no skirt such as 24 provided.

After the closure member 21 has been moved downwardly into engagement with the lower seat 22, the water from the low pressure source of supply entering through the passage 9 unseats the check valve I6 and flowsto the press cylinder through the opening I4 leading from the central portion 6 of the chamber within the valve. As the press cylinder is ascending, the pressure within the central chamber 6 is appreciably lower than the low pressure source of supply. The fluid under high pressure seeking admission to the central chamber 6 through the passage I3 and the passage extending through the member 52 is nevertheless prevented from entering by means of the'valve 54. Since the valve seat 53 opens outwardly, the high pressure fluid maintains the valve 54 onits seat and the passage throughthe seat 53 closed. In addition'tothe high pressure fluid acting on'thevalve'54 main-- tainingit inclosed position, the spring 51 urging the piston- 56 downwardly acts-through the rocker arm 6l tolikewise urgethe-yoke 'andthe attachedvalve54 upwardlyagainst the seat 53.-

When now thepress plunger reachesthe limit of itstraveland" the pressure within the chamber 6 builds up to substantially the value of the ill low pressure source of supply, thisincrease in pressure acting on the lower face of the piston 56 willovercome the action ofthe spring 51 and thehigh pressure fluid on the valve 54 so that such valve will be unseated, admitting fluid from the highpressure source of supply to the chamber Sand" consequently through the opening- 14 tothe press cylinder. As'soon as fluid from" the high-pressuresource of supply is ad mitted to the-valve, the check'valve 16 will drop closing the passage from the value to the chamber 9 so that the high-pressure fluid will be prevented from backing'up into the low pressure line;

' The generalvalve'assembly and its associatedcontrol mechanism shown in Fig. 2 connected to the press 62 by means of a pipe 62a embodies the same main valve assembly illustrated in Fig. l'and just described. The only principal difierence between the "arrangement illustrated in Figs.

1 and'2 are thelow pressure check valve generally indicated" at l6a, high pressure check valve generallyindicated-at 63"; the'waste check valve generally indicatedat 64 and the control valve generally indicated at 65.- Similar reference this point.

rounding the low pressure inlet against'which' characterswill, therefore, be employed to designate parts which are identical in both Figs. 1' and 2.

The check valve l6a is of such special construction' as to require special consideration at It' will be noted that the wall surof the cylindrical extension I6. This construction is particularly provided in order to provide in the operation of the check valve an inherent dash-pot operation; that is; when the check valve l6a dropsontoits seat [5a, the entry 1 of'the.cylindricalportlon l6 into the cylindrical bore provided therefor" will provide a snubbing action similar to a conventional'dash-pot.

The checkvalve 63comprises a casing 66 having a threaded extensionliTby means of which the same maybe secured'to: the main valve body. Theicasing 66'is provided with a central chambergenerally 'indicatedat 68 to which fluids from a sourceof' high pressure: isadmitted by means of a conduit 69 and from which such fluid flows to themain valve chamber through the passage 16in the extension. 61. "Positioned within the casing 68of;the check valveis an annular valve seat generally indicated at 1| against which thereis urged a closure piston 12 underthe in- 1 fluence of springs 13."

The piston 12 and the valve'seat are eachprovided with annular inserts 1la'and 1lb'formed of some hard wear-resistant material so'that a perfect seat may be maintained .without frequent ree-facing; The upper end into which the closure piston 12 extends. About the closure piston "where it enters the plug 14 is a packing gland 15 which prevents the leakage of high pressure fluid upwardly past the piston 12. The upper end of the spring 13 seats against a plate 16 which is maintained in adjusted position by means of a set screw 11.

When the pressure within'the chamber 6 of the main valve is lower than substantially the pressure of the low pressure fluid source of supply, the spring 13 will maintain the piston 12 in engagement with the valve seat 1|, thereby preventing the fluid under high pressure from the conduit 69 from passing to the chamber 6 through the passage 10. Due to the direction in which the valve 1| faces, the high pressure fluid does not have a tendency to unseat the piston 12. The strength of the spring 13 is such, however, that when the pressure within the chamber 6 and the passage 10 amounts to substantially that of the low pressure fluid supply, the piston 12 will be moved upwardly on from its seat 1l admitting the fluid under high pressure to the chamber 6. It is frequently desirable to arrest at any point the movement of the press cylinder either in its upward or downward travel and to this end, I provide the waste check valve 64; This waste check valve comprises a piston" at its upper end provided with a valve seat 19 adapted to engage avalve seat and close the passage therethrough. At this point it may be noted that the casing 8| which carries the waste check valve is substituted in the main valve'assembly, as illustrated in Fig. 1, for the lower head In which carries the lower main valve thimble 20.

The piston 18 is supported in and guided by a cylindrical opening in the lower end of the casing 8|, which opening is closed'by means of the nut 82. A piston arm 83 is connected to the piston 18 and at its lower end is connected to a pressure head 84. A frame generally indicated at and including acup-shaped head 86 supports a diaphragm 81 against which the pressure head 84 bears. The frame 85 may be secured to the nut 82 or more particularly the casing 8|, in any suitable manner as shown. Connected with the head 86 is a fluid supply pipe 88 through which fluid under pressure may be introduced to the space definedby diaphragm 81 and the head 86 to force the pressure'head 84 upwardly and thus move the piston 18 upwardly until it engages the valve seat 80 and closes the passage therethrough.

The conduit 89 connected to the casing 80 will carry away the waste water from the valve.

In Fig. 2, as shown, a conduit 90 is connected withthe head 31 of the main valve for introducing fluid under pressure to the space defined between the diaphragm 38 and the head 31 so that when fluid is thus introduced to such space, the closure member 21 may be manipulated in the manner explained in connection with the description of Fig. 1.

The conduits 88 and 90shown in Fig. 2 are connected through the control valve generally indicated at 65 to a compressed air tank 9|. The construction of the valve 65 will be more clearly apparent by having reference to Fig. 9.

As illustrated in Fig. 9, the valve 65 comprises a casing 92 having a central bore extending entirely therethrough and within which there is positioned a cylindrical lining 93. The central bore of the casing 92 is enlarged in three axially spacedareas denoted at 94, 95 and 96 respectively. Thecasingwz in the" areas of the-en- Ill) largements 94 and 95 is provided with apertured bosses 96 and 91 respectively. The bosses are internally threaded so as to receive the ends of the conduits 90 and 88 as shown in Fig. 2. The

casing 92 is likewise provided with an apertured boss 98 opposite the enlargement 96 in the bore and into such last-named apertured boss there is screwed a pipe 99 connecting the valve 65 with the air tank 9|.

The sleeve or lining member 93 is provided with a series of axially spaced apertures I00, I0l and I02, respectively, affording communication between the conduits 88, 90 and 99 and the interior of the sleeve 93.

Within the sleeve 93 there is slidably mounted a valve including two spaced cupped washers I03 and I04 formed of some suitable flexible gasket material suchas leather, rubber, etc. Associated with each of the cups or gaskets I03 and I04 respectively are cup shaped metallic securing means I03a and I04a. These securing cups extend axially and radially over the edges of the flexible cups I03 and I04 so as to prevent the latter from moving into the openings IOI, I02 and I03 while being moved past the same. The diameter of the valve between the spaced cups is less than the diameter of the sleeve 93 so that when the parts are in the position illustrated in Fig. 9, the air from the pipe 99 may flow through the valve 65 to the pipe 88. The valve within the lining 93 is connected by means of a suitable rod I to a manipulating handle I06, the latter being pivotally supported by means of a bracket I01 carried by the upper extension of the sleeve 93. The sleeve 93 is also provided with apertures therethrough at I08 whereby any fluid under pressure in the conduit 90 may escape to the outer atmosphere when the parts are in the position illustrated in Fig. 9.

The various elements of the valve 65 are so proportioned that when the handle I06 is moved from the position illustrated in the drawings to the position generally indicated by the line I09, the gasket I04 will have moved upwardly toa position between the openings I00 and I02 and the gasket I03 will be in a position between the openings IOI and I02. When the handle I06 is, therefore, in'the position indicated by the line I09, the air from the pipe 99 will be prevented from flowing to either pipe 88 or 90 and both of such last-named pipes will be in communication with the atmosphere. If now the handle is moved downwardly to the position indicated by the line IIO, the gasket I04 will be in a position between the openings I00 and I02 and the gasket I03 will have moved upwardly into a position between the openings IOI and I08. When the handle I06 is, therefore, in this last-named position, the air tank 9| will be connected through the conduit 90 to the space between the diaphragm 38 and the head 31 of the main valve.

In the light of the foregoing, it will be noted that when the handle is in the full line position illustrated in Fig. 9, the piston 18 will be forced upwardly into engagement with the valve seat 80 closing the passage therethrough and since the conduit 90 is not connected to the air tank but instead to the opening I08 vented to the atmosphere, the spring 42 will maintainthe closure member 21 in the position illustrated in Figs. 1 and 2. When the handle I06 is in the up position, therefore, any fluid within the press cylinder will be trapped therein so that the pistonoi the press will be held in the position which it occupied at the time the handle I06 was moved to the up position.

Assume now that the handle I06 is moved to the intermediate position, i. e., that represented by the line I09 and as illustrated in Fig. 2. Both conduits 8B and 90 will now be vented to the atmosphere so that the valve will be entirely deenergized and the parts will occupy the position illustrated in Fig. 2.

Assuming now that the handle I06 is moved to the down position, as denoted by the line I I0 in-Fig. 9. The pipe 90 will then be connected to the air tank SI and the pipe 88 will be vented to the outside atmosphere, the piston 18 will remain in the position as illustrated in Fig. 2, but the closure member 21 will move downwardly from engagement with the seat 30 into engagement with the seat 22. The valve will, therefore, conmeet the press with the low pressure source of fluid; and the press will remain so connected until the piston reaches the limit of its travel, whereupon the pressure within the chamber 6 will build up to a point suflicient so that fluid from the high pressure source of supply will be admitted to the press in the manner previously explained.

Instead of employing fluid pressure means for moving the closure member 21 from the valve seat 30 into engagement with the valve seat 22, as illustrated in Figs. 1 and 2, I may use mechanical means as illustrated in Figs. 3 to 6 for accomplishing this purpose. In Figs. 3 and 4 only so much of the main valve assembly as need be shown for an understanding of this modification has been illustrated and like reference characters will be employed to designate the parts of the main valve assembly illustrated in Fig. 1 which are shown in Figs. 3 and 4. In Figs. 3 and 4 the closure member 21 is shown connected to an actuating stem III which, at its upper end, extends into a movable plunger H2. The plunger II2 extends out of the chamber 4 and a gasket H3 is employed to prevent leakage of the fluid from the valve chamber past the plunger. The stem II is secured in the plunger II2 by means of a nut I I4 which, as most clearly illustrated in Fig. 6, is, at its upper end, provided with a recess H5. The stem I I I is provided with an enlarged head II6 so that a limited amount of relative axial movement between the stem III and the plunger I I2 may take place in the manner and for the purpose hereinafter more fully explained.

Any suitable means such as a cam II1 carried by shaft I I8 may be employed to move the plunger I I2 downwardly from the position illustrated in Fig. 4 to the position illustrated in Fig. 3. At

' this point, it should be noted that the diameter of the plunger I I2 where it passes out of the casing of the valve is greater than the efiective diameter of the closure member 21, so that the fluid under pressure in the chamber 4 tends to maintain the parts in the position illustrated in Fig. 4 until the cam II1 moves the same into the position illustrated in Fig. 3.

When the shaft I I8'is rotated causing the cam II1 to force the plunger II2 downwardly in the manner illustrated in Fig. 3, the parts are so 'proportioned that the closure member 21 moves into engagement with the valve seat 22 shortly before the plunger II2 reaches the limit of its travel under the influence of the cam. After the closure member has thus become seated, further movement of the plunger I I2 is permitted by the head I I6 of the rod I I2 moving upwardly in the space II5, as illustrated in Fig. 5. When the cam II1 is,.theref.ore,-inthe. position illustrated. inv Fig. 3,

aha-plunger I I2:-is heldin'such a position that it exertsno axial force-upon the stem:III. The

pressure within the chamber 6 will then maintain the closure member 21 in engagement with the-valveseat 22. 1

The employment of the means illustrated in Figs. 3 to 6, both inclusive, for actuating the closure member 21 makes it possible to control a plurality of valves from a single shaft such as I I0. This is particularly advantageous when a bank of presses is operated from a single control station.

It will be noted that in the form of main valve assembly as illustrated in Figs. 1 and 2, the high pressure supply check valve associated therewith has been functionally responsive upon the building up of pressure Within the main valve chamber to immediately and automatically cut in the high pressure fluid as soon as the press piston reaches the limit of its travel. It is frequently desirable when curing certain rubber products to have the early stages of the cure proceed while the press is held closed by low pressure and to cut in the high pressure only during the latter stages of the cure. To this end, I provide a high pressure check valve such as is illustrated at H9 in Fig. 7.. The check valve I I9 is, in many respects, similar to the check valve 63 and, therefore, like reference characters will be employed to designate like parts. The principal difference between the check valve '63 and H9 is that the latter, instead of employing a spring to maintain the piston 12 in engagement with the valve seat II, utilizes a connecting rod I20 at its lower end secured to the piston 12 and at its upper end secured to a pressure head I2I. The plug 14 carries a frame generally indicated at I22 which supports a cup-shaped head I23 and a diaphragm I24. Connected to the head I23 is an air pipe I25 by which air may be introduced to the space between the diaphragm I24 and the head I23 to force the piston I2 downwardly into engagement with the seat II and to close the passage therethrough. When the high pressure line check valve such as! I9 is employed, the piston 12 may be maintained on its seat for any desired length of time after the press is closed and such piston may be moved off of its seat at any time during the cure to admit the high pressure fluid to the press cylinder.

For certain types of operation as hereinafter more fully explained, it may be desirable to include in the main valve assembly an independently controllable check valve such as I26 wherebythe flow of low pressure fluid to the main valve and more particularly to the press may be controlled independently of the main closure member 21. The valve I26, as illustrated in Fig. 7, comprises a bodygenera-lly indicated at I21 connected in the low pressure supply pipe I21a within which there is a partition I28 having a passage therethrough which may be closed by the plate I29. The plate I 29 is connected to a stem I30 which passes out of the valve body thorugh the packing gland I3I and to the upper end of which there is secured a pressure head I32. A frame generally indicated at I 33 supported by the body I21 carries a diaphragm I34 anda cupshaped head I35. A pipe I36 is connected to the head I33 so that air or other suitable fluid under pressure may be introduced to the space between the diaphragm I34 and the head I to force the plate I29 into engagement with the partition I28 and thus close ofi the flow .of .fluidjromthe low..pressure,..source of supply. ..In;;Fig. 10' there isdiagrammaticallyrepre- ..sented.a..com'plete vcontrol system for hydraulic presses embodying the several previously described Lfeatures .of .my invention. The main .valve.'I,..the.,high,pressure line check .valve II9, the waste valve 64 and'the low pressure inlet valve I26 and the control valve 65 which have all been described in detail are merely diagrammatically represented.

In addition to the conduits 88 and 90 connected to the control valve 65, as previously explained, there are included a time delay control valve I31, a hand-operated valve I38, a conduit I39, a branch conduit I40 and a conduit I4I, all connected as clearly shown in the drawings, so that air or suitable fluid under pressure from the container or tank 9Ia may be utilized in the manner presently to be explained in variously manipulating the valve assembly so that a proper control may be had over the press.

At this point it may be well to note that the conduit I2'Ia is connected to a source of low fluid pressure; the conduit 69 is connected to a source of high fluid pressure; conduit 62a is connected to the press and the conduit 89 is connected to a waste.

The time delay control valve I3! is connected by means of a link I42 to the lever I06 and such valve is so constructed that at the expiration of a predetermined time interval after either the handle I06 is raised to the upper position or after the pressure in the conduit 62a builds up to a predetermined value, i. e., approximately to that of the pressure within the conduit I21a, such time delay control valve will close off the air supply to the pipe I25, 1. e., the check valve H9, and vent such valve to the atmosphere so that communication is established between the high pressure fluid supply and the press.

The valve I38 which is preferably hand-operated is employed for the purpose of controlling the low pressure supply valve I26.

From the foregoing it will be apparent that the operator, by a simple manipulation of the handle I06 and/or the valve I38, may control the operation of the press in any desired manner.

Other modes of applying the principle of my invention may be employed instead of the one explained, change being made as regards the apparatus herein disclosed, provided the means stated in any of the following claims, or the equivalent of such stated means be employed.

I therefore particularly point out and distinctly claim as my invention:

1. A control valve for fluid-operated presses and the like comprising a casing having a chamber therein and provided with passages by which said chamber may be connected with a source of relatively low fluid pressure, a drain, a source of relatively high fluid pressure and a press cylinder, axially spaced annular valve seats facing toward each other in said chamber, a movable closure member adapted to alternately engage said valve seats and close the passage therethrough, and another closure member movable independently of said first-named closure member and adapted to engage and close the passage through one of said valve seats.

2. Control means for fluid operated presses and the like including a valve comprising a casing having a chamber therein and provided with passages by which, said chamber may be connected with a source of relatively low fluid pressure, a, drain, a source of relatively high fluid 1 pressure and a press cylinder, axially spaced annular, valve seats in said chamber, a movable closure member adapted to alternately engage said valve seats and close the passage therethrough, another closure member movable independently of said first named closure member and adapted to engage and close the passage through one of said valve seats, and means for selectively independently and simultaneously moving said closure members.

ARCHIBALD F. SINCLAIR. 

